Description : Velocity of the thermal neutron (< 0.025 eV) used for fission of U-235 is around __________ m/sec. (A) 1 (B) 2200 (C) 3 × 10 11 (D) 9 × 10 21
Last Answer : (B) 2200
Description : The velocity of thermal (slow) neutrons triggering nuclear fissionreaction (having energy equal to 0.025 eV) is about __________ metres/second. (A) 1100 (B) 2200 (C) 3300 (D) 4400
Description : Heat is generated in a nuclear reactor (thermal) by (A) Combustion of a nuclear fuel e.g. uranium (B) Fusion of atoms of uranium (C) Absorption of neutrons in uranium atoms (D) Fission of U-235 by neutrons
Last Answer : (D) Fission of U-235 by neutrons
Description : Number of secondary neutron emitted on fission of an atom of U-235 by slow neutron bombardment is (A) 3 (B) 235 (C) 200 (D) 92
Last Answer : (A) 3
Description : A uranium nucleus `.^(235)U` liberates 200 MeV per fission 1.5 kg of uranium reacts during explosion of a uranium bomb. What is the mass of an equival
Last Answer : A uranium nucleus `.^(235)U` liberates 200 MeV per fission 1.5 kg of uranium reacts during explosion of a uranium ... TNT is `4.1 xx 10^(6) J//kg` ?
Description : Calculate the energy released by fission of 1 g of `._(92)^(235)U`, assuming that an energy of 200 MeV is released by fission of each atom of `.^(235)
Last Answer : Calculate the energy released by fission of 1 g of `._(92)^(235)U`, assuming that an energy of 200 MeV is ... `= 6.023 xx 10^(26) kg mol^(-1)`)
Description : Nuclear fission of one atom of uranium-235 produces the energy equivalent to about __________ MeV. (A) 20 (B) 200 (C) 500 (D) 2000
Last Answer : (B) 200
Description : Out of the following, nucleus of __________ atom contains the largest number of neutrons. (A) U-235 (B) U-238 (C) U-239 (D) Pu-239
Last Answer : (C) U-239
Description : A metal wire of 0.01 m dia and thermal conductivity 200 W/m.K is exposed to a fluid stream with a convective heat transfer coefficient of 100 W/m2 .K. The Biot number is (A) 5.6 (B) 0.025 (C) 3.5 (D) 0.0035
Last Answer : (B) 0.025
Description : What are thermal neutrons ? Thermal neutrons are slow neutrons (having energy below 1 eV) which are in thermal equilibrium with their surroundings.
Last Answer : Thermal neutrons are slow neutrons (having energy below 1 eV) which are in thermal equilibrium with their surroundings.
Description : The reaction `._(92)U^(235) + ._(0)n^(1) rarr ._(56)Ba^(140) + ._(36)Kr^(93) + 3 ._(0)n^(1)` represents a)Artificial radioactivity b)Nuclear fission c
Last Answer : The reaction `._(92)U^(235) + ._(0)n^(1) rarr ._(56)Ba^(140) + ._(36)Kr^( ... radioactivity B. nuclear fission C. nuclear fussion D. none of the above
Description : Which of the following undergoes fission reaction easily? (A) U-235 (B) U-238 (C) Th-232 (D) None of these
Last Answer : (A) U-235
Description : Thermal nuclear reactors using enriched uranium as fuel contains a maximum of __________ percent fissile material i.e. U-235. (A) 1 (B) 2 (C) 3 (D) 7
Last Answer : (C) 3
Description : Atoms of U-238 and U-235 differ in structure by three (A) Electrons and three protons (B) Protons (C) Neutrons (D) Electrons
Last Answer : (C) Neutrons
Description : A reaction develop nuclear energy at the rate of `3 xx 10^(4) kW`. How many atoms of `.^(215)U` undergo fission per second? How much `.^(235)U` is bur
Last Answer : A reaction develop nuclear energy at the rate of `3 xx 10^(4) kW`. How many atoms of `.^(215)U` ... constant is `6.023 xx 10^(26)` per kg mole)
Description : The principle behind a breeder reactor is: w) U-235 undergoes fission. x) U-238 is converted to Pu-239, which undergoes fission. y) Deuterium undergoes fission. z) Cobalt-60 undergoes fission.
Last Answer : ANSWER: X -- U-238 IS CONVERTED TO Pu-239, WHICH UNDERGOES FISSION.
Description : A thermal nuclear reactor compared to a fast breeder reactor (A) Uses slower neutrons for fission (B) Uses faster neutrons for fission (C) Gives higher power density (D) Requires less fuel to run at the same power level
Last Answer : (A) Uses slower neutrons for fission
Description : The number of neutrons accompanying the formation of `._(54)Xe^(139)` and `._(38)Sr^(94)` from the absorption of a slow neutron by `._(92)U^(235)`, fo
Last Answer : The number of neutrons accompanying the formation of `._(54)Xe^(139)` and `._(38)Sr^(94)` from the ... `._(92)U^(235)`, followed by nuclear fission is
Description : In the neutron`-`induced fissioin reaction of `._(92)U^(235)` one of the products if `._(37)Rb^(95),` in this mode, another nuclide and three neutrons
Last Answer : In the neutron`-`induced fissioin reaction of `._(92)U^(235)` one of the products if `._(37)Rb^(95),` in this ... `._(55)^(145)Co` D. `._(54)^(143)Xe`
Description : A fast breeder reactor (A) Utilises fast neutrons for causing fission (B) Converts fertile material (e.g., U-238) into fissile material (Pu-239) (C) Normally employs molten sodium as coolant (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : An element having large number of __________ is most easily subjected to nuclear fission. (A) Protons (B) Electrons (C) Neutrons (D) Nucleons
Last Answer : (D) Nucleons
Description : Quantity of fissionable material (i.e. U-235) in natural uranium is __________ percent. (A) 0.71 (B) 6.31 (C) 99.29 (D) 12.73
Last Answer : (A) 0.71
Description : Which type of Uranium is used in the fission process? A. Uranium – 234 B. Uranium - 235 C. Uranium - 236 D. Uranium - 237
Last Answer : ANSWER: B
Description : One international unit (I.U) of vitamin D is defined as the biological activity of (A) 0.025 µg of cholecalciferol (B) 0.025 µg of 7-dehydrocholecalciferol (C) 0.025 µg of ergosterol (D) 0.025 µg of ergocalciferol VITAMINS 113
Last Answer : Answer : A
Description : U-235 content in enriched uranium, that is normally used in power reactors (e.g., at Tarapur atomic power plant), is about __________ percent. (A) 85 (B) 50 (C) 3 (D) 97
Description : Candu reactor is a __________ nuclear reactor. (A) Natural uranium fuelled heavy water cooled & moderated (B) Highly enriched uranium (85% U-235) fuelled (C) Homogeneous (D) Fast breeder
Last Answer : (A) Natural uranium fuelled heavy water cooled & moderated
Description : Liquid metal (e.g., molten sodium) is preferred as a coolant in case of a/an __________ reactor. (A) Homogeneous (B) Graphite moderated (C) Fast breeder (D) Enriched uranium (3% U-235) fuelled
Last Answer : (C) Fast breeder
Description : Fast breeder nuclear reactors using enriched uranium as fuel may contain upto a maximum of __________ percent of U-235 (i.e. fissile material). (A) 15 (B) 45 (C) 65 (D) 85
Last Answer : (D) 85
Description : Torque and bending moment of 100 kN.m and 200 kN.m acts on a shaft which has external diameter twice of internal diameter. What is the external diameter of the shaft which is subjected to a maximum shear stress of 90 N/mm2? a. 116.5 mm b. 233.025 mm c. 587.1 mm d. 900 mm
Last Answer : c. 587.1 mm
Description : A fast reactor uses: w) an extremely short time to get to the maximum operating reactivity. x) uranium-235 as fuel. y) heavy water as a coolant. z) essentially unmoderated neutrons.
Last Answer : ANSWER: Z -- ESSENTIALLY UNMODERATED NEUTRONS.
Description : Energy produced in the nuclear fission is of the order of __________ MeV. (A) 20 (B) 200 (C) 1000 (D) 2000
Description : Reactors in commercial nuclear power plants in the U.S. are often referred to as thermal reactors. A thermal reactor uses: w) fissionable plutonium-239 as fuel. x) a relatively low heat output. y) neutrons moderated to relatively low energies. z) liquid sodium as a coolant.
Last Answer : ANSWER: Y -- NEUTRONS MODERATED TO RELATIVELY LOW ENERGIES.
Description : Fast breeder reactors do not (A) Use Th-232 as fissile fuel (B) Convert fertile material to fissile material (C) Use fast neutrons for fission (D) Use molten sodium as coolant
Last Answer : (A) Use Th-232 as fissile fuel
Description : Which of the following accounts for the maximum energy release in the nuclear fission process? (A) Kinetic energy of fission products (B) Radioactive decay of fission products (C) Instantaneous release of γ-rays (D) Kinetic energy of neutrons
Last Answer : (A) Kinetic energy of fission products
Description : The main purpose of control rod in a nuclear reactor is to control the (A) Chain reaction and hence the power output by regulating the number of secondary neutrons causing fission (B) ... radiation (C) Conversion of fissile material into fertile material (D) Velocity of the secondary neutrons
Last Answer : (A) Chain reaction and hence the power output by regulating the number of secondary neutrons causing fission
Description : The number of neutrons accompanying the formationof 54Xe 139 and 38Sr 94 from the absorption of a slow neutron by 92U235 , followed by nuclear fission is (A) 1 (B) 2 (C) 3 (D) 4
Description : Enriched uranium means that, it contains (A) More than 0.71% of U-235 (B) Only fertile material (C) Only fissile material (D) No impurities
Last Answer : (A) More than 0.71% of U-235
Description : Assume a frequency range of 405.0125 MHz to 405.0875 MHz and 25 kHz channeling plan, determine the center frequency of the second channel from the lower limit. A. 405.030 MHz B. 405.025 MHz C. 405.050 MHz D. 405.075 MHz
Last Answer : C. 405.050 MHz
Description : Assume a frequency range of 401.000 MHz to 401.050 MHz, if you apply 25 kHz channeling plan, determine the center frequency of the first channel from the lower limit. A. 401.010 MHz B. 401.0125 MHz C. 401.025 MHz D. 401.00625 MHz
Last Answer : B. 401.0125 MHz
Description : When the nurse notes that the post cardiac surgery patient demonstrates low urine output (< 25 ml/hr) with high specific gravity (> 1.025), the nurse suspects: a) Inadequate fluid volume Urine ... by high urine output with low specific gravity. d) Anuria The anuric patient does not produce urine.
Last Answer : a) Inadequate fluid volume Urine output of less than 25 ml/hr may indicate a decrease in cardiac output. A high specific gravity indicates increased concentration of solutes in the urine which occurs with inadequate fluid volume.
Description : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The neutrons from the source are of high speed and en
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission ... neutrons C. magnetic neutrons D. electric neutrons
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... water B. Graphite C. Beryllium D. Sodium
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... mass number only D. be all the above three
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission ... . absorbs thermal energy. Produced in the reactors
Description : Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission? (1) Boron (2) Heavy water (3) Uranium (4) Plutonium
Last Answer : (1) Boron Explanation: Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and ... aluminium. Crystalline boron is chemicallyinert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
Description : wo elements which are used to absorb neutrons to control the chain reaction during nuclear fission are - (1) Boron and Cadmium (2) Boron and Plutonium (3) Cadmium and Uranium (4) Uranium and Boron
Last Answer : (1) Boron and Cadmium Explanation: Since the continued chain reaction of a nuclear fission reactor depends upon at least one neutron from each fission being absorbed by another fissionable nucleus, the ... and then the control rods are slowly lifted until a chain reaction can just be sustained.
Description : The part of the nuclear reactor that controls the speed of neutrons released during nuclear fission is
Last Answer : moderator.
Description : The two elements which are used to absorb the neutrons in nuclear fission during chain reaction
Last Answer : Boran and Cadmium